Doosan machines with 50- to 75-horsepower engines have been Interim Tier 4 (iT4) compliant since 2008. For Doosan machines that are not subject to iT4 or Tier 4 compliancy until future dates, Doosan is committed to incorporating iT4 and Tier 4 technologies that provide the most benefits to our customers and are the most applicable to the products that we manufacture.

Machines in the 175 – 600 horsepower class will be compliant to federal iT4 emission standards in 2011. In addition, Doosan machines that fall into the 75- to 175-horsepower class will become iT4 compliant in 2012.

An engine technology that Doosan already utilizes extensively on higher horsepower engines is high-pressure common rail (HPCR) fuel injection systems. HPCR was applied to many models of Doosan equipment during Tier 3 and will be an enabler for application of further technologies needed for iT4 and Tier 4 compliancy, such as diesel particulate filters (DPF), diesel oxidation catalysts (DOC) or selective catalytic reduction systems (SCR).

Doosan products are currently in compliance with federal emission regulations and will continue to be in the future when deadlines for new regulations are reached. In 2010 Doosan collaborated with our dealer network to prepare staff to assist customers with their emission related questions and concerns and provide the necessary information and education to customers. Public literature explaining all emission regulations, including iT4, along with future emission related technologies is also available. In 2011, Doosan’s public website will also contain this information. As 2011 progresses, Doosan will continue to provide further emission related information as necessary to keep our customers informed and educated on our progression through this endeavor.

Doosan products such as the DX60R compact excavator, the DX80R compact excavator and the DX55W wheeled excavator have already been iT4 compliant for quite some time. These products had very minor increases in price due to iT4. In some other cases, advancements needed in engines and other systems external to the engine for IT4 will add expense.